C5 X7 parking sensor ECU faulty?

[Viitonen]

The parking sensors are totally out of order. It shows a warning that there is a problem with the system.

So, I connected the car with diagbox and it came with fault code F085 (fault no communication with the parking assistance ECU).

Checked from the fuse box index that there is no fuse for just parking assistance, it affects to other things too, which are working properly.

Where would you start checking for the problem? Where is this ECU located? I’ve a X7 saloon.

[GiveMeABreak]

The parking assistance ECU on the saloon is to the left of where the spare wheel is. Lift up the boot lining and remove the spare wheel. There you will see a black box on the right hand side bolted on. This is the parking assistance ECU.

Be wary if any liquid from containers has leaked onto the unit. I had nearly 5 litres of screenwash, where the cap came loose and soaked the ECU - I was not even aware until I had the errors as it had seeped under the boot mat. I could tell as the screen wash was purple and had gone into the ECU.

I managed to use lots of electrical contact cleaner after very carefully opening up the box and cleaning the circuits. It took several hours and many attempts to completely clean and dry it out.

It works fine now.

[Sloppysod]

Hi, The Sensor ECU my 2011 X7 it is behind the left hand boot lining, in a small 'rack' for various ECu's

[GiveMeABreak]

That's the TPMS ECU then Stu.

Rear Left hand side looking into tailgate: TPMS ECU, Trailer ECU Module (BSR) and I believe the Aerial for the TPMS system too.

Spare Wheel Bay: Parking Assistance ECU bolted onto right hand side of spare wheel recess.

Rear Right hand side: Subwoofer (part of HiFi pack) and / or CD-Changer if fitted as options.

[Viitonen]

Woah! Lots of ECU abbrevations you’ve got
But I’ll check the spare wheel recess. Thank you!

[Hell Razor5543]

Don't you just hate MLAs?

[Sloppysod]

That's the TPMS ECU then Stu.
Rear Left hand side looking into tailgate: TPMS ECU, Trailer ECU Module (BSR) and I believe the Aerial for the TPMS system too.
Spare Wheel Bay: Parking Assistance ECU bolted onto right hand side of spare wheel recess.
Rear Right hand side: Subwoofer (part of HiFi pack) and / or CD-Changer if fitted as options.

I was sure I was right especially as I have upgraded from just rear to front and rear. As you can see in the photo there are just mounting studs in the spare wheel well on mine, the parking ECU is in the 'rack' along with the other ECU's as mentioned in Marcs earlier post.

[GiveMeABreak]

That's exactly where it is supposed to be Stu As you can see from the mounting pins from your pic.

Not sure what happened there, but even Citroen Service for your car show it in the same place as it is supposed to be:

Never mind- at least you have one!